Method for denoising three-dimensional laser scanning point cloud data of shield tunnel

Abstract

The invention relates to a method for denoising three-dimensional laser scanning point cloud data of a shield tunnel. According to the method, the technical problems of complicated steps, low denoising precision and the like of an existing method for denoising scanning point data are mainly solved. The method provided by the invention is characterized by comprising the following steps: acquiring three-dimensional laser scanning data of the shield tunnel; S1, reading scanning point cloud data, marking an each cycle of scanning point data set as E0; S2, establishing a Cartesian rectangular coordinate system and partitioning scanning point quadrants; S3, extracting the scanning point cloud data; S4, carrying out preliminary elimination on noisy points according to structural features of the shield tunnel and scanning features of a three-dimensional laser scanner based on X values or Y values of different quadrants and the distance change trend; S5, carrying out circle fitting secondary elimination on the scanning point data subjected to preliminary elimination of the noise points; S6, carrying out final denoising of the three-dimensional laser scanning point cloud data by an ellipse fitting method performed on the basis of a geometrical distance least square method; S7, repeating the steps of S2, S3, S4, S5 and S6, and treating all point cloud data of all scanning cycles; S8, outputting effective point cloud data of the scanning points.

Description

technical field [0001] The invention relates to a method for denoising point data of three-dimensional laser scanning, and in particular discloses a method for denoising point cloud data of three-dimensional laser scanning of subway shield tunnels, which is applied to the field of shield tunneling engineering. Background technique [0002] Due to the advantages of fast scanning speed, large amount of collected data, non-contact measurement, high precision, and high resolution, 3D laser scanning technology has been more and more used in shield tunnel operation detection operations, such as shield tunnel deformation Convergence detection, limit detection analysis, wrong platform and seam detection, etc. However, affected by factors such as its measurement method, the internal structure of the shield tunnel (such as cables, lighting system appliances, escape devices, track plates, steel rails, etc.), external interference, etc., there will inevitably be a lot of errors in the p...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to design a method for denoising point cloud data of shield tunnel 3D laser scanning, which mainly solves the technical problems of existing scanning point data denoising methods such as complicated steps and low denoising accuracy.

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